Daniel Gilbert gives a well-appreciated lecture in which he likens the human mind to a bad scientist, everything from biased exposure to data and biased analysis of information to outright forgery. Hidden here is a deeper point. Science progresses precisely because it has a series of anti-deceit-and-self-deception devices built into it, from full description of experiments permitting exact replication, to explicit statement of theory permitting precise counter-arguments, to the preference for exploring alternative working hypothesis, to a statistical apparatus able to weed out the effects of chance, and so on.

Laurence C. Smith--

The sea-ice collapse, however, changed my mind that it will be decades before we see the real impacts of the warming. I now believe they will happen much sooner.

Let's put the 2007 sea-ice year into context. In the 1970's, when NASA first began mapping sea ice from microwave satellites, its annual minimum extent (in September, at summer's end) hovered close to 8 million square kilometers, about the area of the conterminous United States minus Ohio. In September 2007 it dropped abruptly to 4.3 million...

The ensemble averages of our most sophisticated climate model predictions, put forth in the IPCC AR4 report and various other model intercomparison studies, don't predict a downwards lurch of that magnitude for another fifty years.

...Over the past three years experts have shifted from 2050, to 2035, to 2013 as plausible dates for an ice-free Arctic Ocean — estimates at first guided by models then revised by reality.

Another one Hanson will like, from Lee M. Silver--

While its mode of expression may change over cultures and time, irrationality and mysticism seem to be an integral part of normal human nature, even among highly educated people. No matter what scientific and technological advances are made in the future, I now doubt that supernatural beliefs will ever be eradicated from the human species.

New results from the labs of Jonathan Pritchard, Robert Moyzis, Pardis Sabeti, and others have suggested that thousands of genes, perhaps as much as ten percent of the human genome, have been under strong recent selection, and the selection may even have accelerated during the past several thousand years.

Out of millions who express sympathy with global jihad, only a few thousand show willingness to commit violence. They tend to go to violence in small groups consisting mostly of friends, and some kin. These groups arise within specific "scenes": neighborhoods, schools (classes, dorms), workplaces and common leisure activities (soccer, mosque, barbershop, café, online chat-rooms).

...Our interviews with friends of the 9/11 suicide pilots reveal they weren't "recruited" into Qaeda. They were Middle Eastern Arabs isolated in a Moroccan Islamic community in a Hamburg suburb. Seeking friendship, they started hanging out after mosque services, in local restaurants and barbershops, eventually living together when they self-radicalized.

Consider the mathematics sections in the USA's National Academy of Sciences: 95% male. Which contributes most to this predominance — higher means or larger variance? One calculation yields the following answer. If the sex difference between the means was obliterated but the variance was left intact, male membership would drop modestly to 91%. But if the means were left intact but the difference in the variance was obliterated, male membership would plummet to 64%. The overwhelming male predominance stems largely from greater variance.

my research shows that 80% to 90% of German physicians do not understand what a positive screening test means — such as PSA, HIV, or mammography — and most do not know how to explain the patient the potential benefits and harms. Patients however falsely assume that their doctors know and understand the relevant medical research. In most medical schools, education in understanding health statistics is currently lacking or ineffective.

even if I agreed with the statement that the climate folks were most probably wrong, I would still opt for the most ecologically conservative stance — leave planet earth the way we found it. Consider the consequences of the very remote possibility that they may be right, or, worse, the even more remote possibility that they may be extremely right.

We had thought income effects are small because we were looking within countries. The GDP differences between countries are enormous, and highly predictive of differences in life satisfaction. In a sample of over 130,000 people from 126 countries, the correlation between the life satisfaction of individuals and the GDP of the country in which they live was over .40 – an exceptionally high value in social science. Humans everywhere, from Norway to Sierra Leone, apparently evaluate their life by a common standard of material prosperity, which changes as GDP increases. The implied conclusion, that citizens of different countries do not adapt to their level of prosperity, flies against everything we thought we knew ten years ago. We have been wrong and now we know it. I suppose this means that there is a science of well-being, even if we are not doing it very well.

Comments and Sharing

Much of what I believed about human nature, and the nature of knowledge, has been upended by the Wikipedia. [...].

Everything I knew about the structure of information convinced me that knowledge would not spontaneously emerge from data, without a lot of energy and intelligence deliberately directed to transforming it. [...]

How wrong I was. The success of the Wikipedia keeps surpassing my expectations. Despite the flaws of human nature, it keeps getting better. Both the weakness and virtues of individuals are transformed into common wealth, with a minimum of rules and elites. [...] With the right tools, it turns out the collaborative community can outpace the same number of ambitious individuals competing.

It has always been clear that collectives amplify power — that is what cities and civilizations are — but what's been the big surprise for me is how minimal the tools and oversight are needed. The bureaucracy of Wikipedia is relatively so small as to be invisible. It's the Wiki's embedded code-based governance, versus manager-based governance that is the real news. Yet the greatest surprise brought by the Wikipedia is that we still don't know how far this power can go. We haven't seen the limits of wiki-ized intelligence. Can it make textbooks, music and movies? What about law and political governance?

Before we say, "Impossible!" I say, let's see. I know all the reasons why law can never be written by know-nothing amateurs. But having already changed my mind once on this, I am slow to jump to conclusions again. The Wikipedia is impossible, but here it is. It is one of those things impossible in theory, but possible in practice. Once you confront the fact that it works, you have to shift your expectation of what else that is impossible in theory might work in practice. [...]

I am convinced that the full impact of the Wikipedia is still subterranean, and that its mind-changing power is working subconsciously on the global millennial generation, providing them with an existence proof of a beneficial hive mind, and an appreciation for believing in the impossible.

"The sea-ice collapse, however, changed my mind that it will be decades before we see the real impacts of the warming. I now believe they will happen much sooner. [...]
Over the past three years experts have shifted from 2050, to 2035, to 2013 as plausible dates for an ice-free Arctic Ocean — estimates at first guided by models then revised by reality."

This is interesting, and very worrying if correct, but then he goes on:

"What does all this say to us about the future? The first is that rapid climate change [...] is a distinct threat not well captured in our current generation of computer models. [...] in the meantime, policymakers must work from the IPCC blueprint which seems almost staid after the events of this summer and fall."

Not at all. If severe climate change is already upon us then there is no point in trying to reduce CO2 emissions - indeed doing anything which wekens the economy could be very damaging indeed.

The whole 'Al Gore' position on climate change hinges on two assumptions. 1. the threat of catastrophic climate change and 2. that this threat can be averted (or significantly ameliorated) if we take significant action *now*.

What Smith is saying is that the second assumption is false, because there is not enough time for any anthropogenic change to ameliorate the situation. So we should *not* proceed on the assumption that there is enough time.

BTW I was rather distrurbed to discover that LCS was surprised at how quickly climate could change - I was reading Nicholas Wade's excellent book Before the Dawn last month, and he mentioned an Ice Age which happened over the space of a decade.

I must admit I was astonished that climate change had happened that rapidly - but then I am not a geography Professor at UCLA like Laurence C Smith!

Just to clarify - I deplore the present focus of the climate change debate, which is mostly concerned with how humans might prevent climate change. I regard it as sheer nonsense (at this time) to assume that humans are able to do anything at all to control global climate, and particular nonsense to imagine that we can adjust the earth's temperature in the direction that suits us best.

Instead I favour a focus on prediction (like Prof Smith's work), and on policies about what we can/ should do if/when climate change happens.

If I may attempt to change Laurence Smith's mind again, globally, we currently have about 1 million sq km more sea ice than is normal for this time of year. (See here - the red line at the bottom is the deviation from the daily 1979-2000 satellite observed average. Ice coverage was indeed much lower than normal earlier in 2007, but by the end of 2007 coverage was higher than normal.)

So if having much less sea ice than normal means catastrophic global warming is upon us, what does much more sea ice than normal mean?

Probably nothing. But the human mind is, as Gilbert says, a bad scientist and I suspect the relative low in sea ice also meant nothing.

(An aside: who wants to take bets on which phenomenon - the peak or the low - gets more media coverage?)

Per the quote by Kahneman, I would question his conclusion that people are comparing their material well being to other countries. While the GDP might seem like a good measure, I suspect, but have not done the work to show, that the optimism about life has more to do with job availability and growth than with the actual GDP of a country. Based on this, the correlation between unemployment rates and life satisfaction may be more helpful.

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